Feature request: Tabbed/multi-project sessions with a project sidebar

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Currently, switching between projects requires either restarting Claude Code in a new directory (losing conversation context) or using /add-dir (which adds scope but doesn't give a clean per-project workspace). There's no way to keep several project sessions open in parallel and switch between them quickly.

Proposed Solution

Support tab-like sessions, each bound to its own project directory, plus a sidebar/menu listing recently used projects for quick switching — similar to browser tabs or an IDE's recent-projects list. This would let users:
Keep multiple project contexts alive at once without losing history
Switch between projects with one click/command instead of restarting
See a persistent list of recently used project folders
Related issues: #19903, #38308, #60151, #1628, #3473 (all about mid-session working directory changes)

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_